Brushed Motor RPM Comparison

Well my friends after my Super Clod Buster didn't go any faster with 15Turn motors in it I decided to check out what the difference was if any between the Holmes Hobbies 15T and Tamiya stock Mabuchi Silver can. I also found an old Tamiya Johnson silver can and an Absima Thrust Eco 15T so decided to test those as well and this is the result.
Reported Specs of the motors.
Mabuchi Silver Can 27T 14000 RPM at 7.2V
Johnson Silver Can 27T 14500 RPM at 7.2V
Homes Hobbies 15T 20880 RPM at 7.2V
Absima Thrust 15T 32000 RPM at 7.2V
This is not a definitive test as the equipment was fairly cheap and in no way calibrated.
My conclusion was that the HH should have been faster being nearly 7000 RPM faster so maybe the torque just isn't there to spin the wheels of such a big rig. But you can draw your own conclusions.
Hope you enjoy!

[RCBirds]

Thanks for showing this test Rob. And you're right, not the absolute numbers, it's the relatives that count.

[AddamsPlayground]

Nice testing! I should get a little setup like that! I am always curious about the actual speeds of the motors and this is a very effective and simple way to test them! Like you said, it is not 110% proven fact but it does give enough feedback to understand which ones have faster rpms so good enough for me! Thanks for sharing the cool video!

[UncleBobsRC]

Hiya Rob, Great video Dude!!!! Most motors spin counter clockwise as you look at them from the output shaft end. The stock motor, the first one you did, at 16, 700 rpm seems to be what I got with my motor dyno, I got 13, 100 to almost 17, 000 RPM's (voltage from 6v to 7.4v). Your little hand held tach seems close enough mate. Love the "bench" for the test... That squeal the Johnson let out might just dry bushings in the motor. The Holmes motor should be zero timing either way it spins, if it had more timing one way or another, the rpm would be way more farther apart, 100's to 1, 000's of rpm's. This is an Awesome test man and you have a ton of motors you can test.... Love test videos like Great Job again my Friend,

[ianat]

Hope you did a full risk assessment now you’re using lasers 😅 great work 👍😃

[mad-beerc]

Hi mate, interesting vid. those little Absima Thrust motors are great for the money! Great budget bangers!

[yodadarksideGreenHawksRC]

Very cool video sir, I enjoyed that.
Those results seemed pretty fair to be honest.
This would be a cool little set up to I have soooo many different motors, it would be great to be able to test them all!
By the way, glad to see I'm not the only one still mainly using brushed motors!
Cheers matey! 👍 👍 👍 👍

[madsrcbuggy]

That was really interesting to watch, Rob! And I think your test rig was great for the comparison purpose, I trust those results!
We still need to figure out why the Hell your Clodbuster wasn't faster than Mark's... I could imagine you try two things: Either you continue to use the Holmes motors in the Clod, and try with a bigger/better battery, I am convinced you will get more speed! Or you could try install the Holmes in a buggy and see how it performs, I would imagine it will be great!
I have Holmes Retro motors in three buggies now, and I love them all, I know I might have a bit of bias towards the brand, ha ha!

[outbackrcaustralia]

G'day Rob😃. That old Johnson motor's in nice condition for its age👌.
Nice test rig mate👍, who cares if it's not super expensive or hi techs, I reckon that was a pretty good comparison Cobber👌🏆. Thanks for sharing your interesting video mate👍🦘🇦🇺

[DustyFingersRC]

Glad to hear the legendary laugh, it was well worth a watch 👍🏻

[JF-RC]

Hi there Rob, a very interesting RPM test, interesting that the Johnson’s 540 motor, was much more free refine than the Mabuchi motor. Best wishes to you and the family 😊😊

[galkawarrior]

Thank you for sharing! I was trying to do my research on how much KV a stock Mabuchi Silver Can 27T is and came across your video. With your findings of 16734 rpm at 7.2 volts, that equates to roughly 2324KV. Someone below claimed they got their motor up to 20, 600 on a freshly charged battery, which is 2861KV. So, for my research, I'll be optimistic and average it up to 2500KV. Again, thank you very much!

[ShenRC]

Hi Rob You have to do try this when testing motors with the laser beam get a pinion gear paint it black and super glue a little sliver across it for the beam to pick up it will be more accurate and you can swap it out to each motor easy this is what I do it works great. nice test. black out near the end.

[rcwreck-creation]

Cheers Rob! That’s quite the set up ya got goin for sure! 👍👌 I like that little device for counting the revolutions. Was it just tape around the motor shafts that the device was picking up?

[barrycheesemore]

Interesting results, and as you said in the description maybe it's a torque issue. RPM is one thing, but if the torque of the motor isn't there it'll defo struggle with the huge wheels and tyres of a Clod!

[mattiasrc]

Interesting little motor test, that rpm-meter seems to be somewhat accurate and for a great price too.

[PeteWylieRC]

Hey what a great idea Rob. I didn't know that such a device existed. What is it actually meant for? So really your Clod should have been quicker than Mark's or is there something about torque that you also need to know? Anyway, interesting video mate 😁👍👍